The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 27, 2001
Filed:
Apr. 21, 1999
Rudolf P. M. Guit, Maastricht, NL;
DSM N.V., Heerlen, NL;
Abstract
Process to separate &egr;-caprolactam from 6-aminocaproamide and 6-aminocaproamide oligomers, wherein &egr;-caprolactam, 6-aminocaproamide and 6 aminocaproamide oligomers are present in a first aqueous starting mixture, which mixture is contacted with an alcohol extraction solvent, resulting in a first aqueous raffinate phase which is poor in &egr;-caprolactam and an alcohol phase which is rich in &egr;-caprolactam and which alcohol phase contains 6-aminocaproamide and/or 6-aminocaproamide oligomers, wherein the latter alcohol phase is subsequently contacted with water (backwash water) resulting in an alcohol extract phase poor in 6-aminocaproamide and/or 6-aminocaproamide oligomers and a second aqueous raffinate phase rich in 6-aminocaproamide and/or 6-aminocaproamide oligomers.